Furnace



Nov. 1924. 1,516,642

4 W.- H. OWEN FURNACE Filed Nov. 10, 1922 Patented Nov. 25, 1%24.

UNETEB STATES WILLIATE HENRY OWEN. OF WIMBLEDON, LQIJDON. ENGLAND.

FURNACE.

Application filed November 10, 1922.

To all whom it may concern:

Be it known that 1, WILLIAM HENRY OWEN, a subject of the King of Great Brit ain, residing at 19, Home Park Road, flim- 5 bledon, S. W. 19, in the county of London, England, h ye invented certain new and useful Improvements in or Relating to Furnaces, of which the following is a specification.

This invention has reference to furnaces and the like fired by liquid fuel and to means therefor and is designed more particularly to ensure improved combustion in furnaces where oil fuel is used on an indus trial scale, such as steanrboiler furnaces, reverberatory furnaces, glass furnaces and the like, and in which pre-heated air is supplied in two different portions and, it may be, at two different temperatures.

According to this invention air which may be pro-heated by the waste gases is divided into two portions, one of which is heated to a higher temperature than the other, the hotter air entering or being injected in immediate proximity to the burner or burners. Both kinds of air are supplied at a point near the base of the flame by an arrangement which may conveniently be concentric with, or symmetrically disposed 30 with regard to each burner or group of burners, so as to enter the furnace as an annulus, or as a ring or symmetrical series of jets. The oil issuing from the burner thus finds itself first bathed as it were in the inner annulus or Zone of hotter air, and hence is eificiently vapourized and prepared for more perfect and complete combustion before mixing with the less heated air, entering by an outer ring or series of. inlets and travelling in a direction parallel with the hotter air. In order to carry this into effect, two heaters are employed one of which called heater A may be nearer to the furnace than the other called heater B. The products of combustion on their way to the chimney pass successively or in series through these heaters and so that A is heated by the hottest waste gases. The whole of the air forcombustion is passed through heater B, on leaving which in a heated condition it is divided into two portions or streams. One of these portions for effecting the full or final combustion, is conducted directly to the furnace-or furnaces into which it is admitted as above referred Serial No. 600,166.

to so that it forms an outer zone around the base of the flame. The other portion or stream of air however submitted to a further l'ieating by being caused to pass through heater A, whereby its temperature is raised still higher because the products of combustion pass first through that heater A. This more highly heated air is conducted to the burners for the purpose described above. It may in fact be termed the vapo-urizing air as distinguished from the other portion which may be termed the combustion air.

Suitable controlling valves are provided to regulate the amount of air passing through each heater.

The heaters may be of the tubular or plate or any other surface type. The air i113 be induced through the heaters and furnaces etc, by the chimney or by a fan or exhauster, or may be forced through by a fan, or blower on its way to the furnace or furnaces. In some cases the vapourizing air supplied to the burners may be caused to pass through heater A only, the other portion for the furnaces passing through heater B, or heater B may be dispensed with altogether, cold air then being admitted direct to the furnace; or heater A may be dispensed with as hereinafter mentioned.

In order that the invention may be clearly understood and readily carried into effect reference will now be had by way of exam ple to the accompanying diagrammatic drawings in which Fig. 1 represents an arrangement suitable for an oil-fired furnace, such as for metallurgical work or for a land boiler.

Fig. 2 represents the application of the invention to a boiler furnace such for in stance as amarine boiler.

Referring more particularly to Fig. 1, A and B indicate two heaters such as above referred to, which in the present instance are built in the base of the flue, or uptake G from the. furnace (or boiler) C which is of any appropriate kind. Said furnace (or boiler) has a combustion space, fire-box or furnace flue D connected with the chim ney O by an opening or passage E, and is provided with an oil burner, sprayer or injector F of any suitable construction, of which there may be two or more if desired. This injector (or each injector) is surrounded by a box or casing G which is con- Lit ell)

nected with. the first or hotter air heater A by a. pipe or passage H, controlled by avalve or valves such as H.

Another pipe or passage 1 (controlled by a valve or valves 1 leads from the second r cooler air-heater B to an annular box or casing I having suitable air-inlets I leading into the furnace or lire-box D.

The said second air-heater B is supplied with atmospheric air through an inlet B and this air after being heated is divided into two portions. Cue these portions of air, viz that which is to form the vapourizing air is led (through a pipe B for instance) into A for the further or second stage heating and then for delivery to the burner through the pipe H. The other or major portion which without further heating is to serve for the complete combustion goes direct through the pipe I and then to the casing l and the opening or inlets I leading into. the furnace.

it will be readily understood that the atomizing oil jet or spray issuing from the injector i commingles at once with the zone of more highly heated air from the central casing, jacket or sheath it and is thereby thoroughly vapourized before it meets and mixes with the zone of less heated air coming through the outer set of inlets or openin 's T The heaters may consist of boxes or casings provided with tubes up which pass the products of combustion from the flue E. The air to be heated is caused to pass (see arrows) in any convenient way, to and fro around these tubes, suitable partitions or baffles being provided where desirable to ause such air to follow a circuitous path and thus ensure effective heating thereof in the well-known manner. If desired instead of tubes, flat parallel plates may be used, as will be obvious.

VV hen the invention is applied to a marine boiler for instance, as in Fig. 2, the heaters A B are placed in the uptake C or in the smoke box, in any convenient position, and are connected to a casing D on the front of the furnace D. The inside of this casing is divided by a partition J into two passages or compartments J J The former of these which is arranged next the boiler and therefore hotter than the other, conducts the more highly heated air to the jacket or casing G of the injector, whilst theother or outer and annular compartment J leads the cooler air to one or more inlet openings by which it enters the furnace. The pipes H and I in this case are connected with the regenerator as in 1.

In some cases the two portions of air may be led separately each through one of the heaters A and B only. Also as before stated heater A may be dispensed with, the air for vapourizing being passed through pipes heated by the furnace itself, the other part of the air for combustion being passed through heater B.

Moreover instead of the oil fuel being supplied through an injector it may be vapourized and mixed with the incoming heated air before reaching the burner.

Obviously the above arrangements may be modified in various ways in carrying the invention into practice without departing from the general nature thereof.

1 claim I l. in an oil-fired furnace, the combination of a burner, and an air-heater heated by tae waste gases from the furnace, means for supplying highly-heated air from said heater to an inner zone immediately around the burner, and means for supplying lesshighly heated air from saidheater to an outer zone around the said inner zone, substantially as described.

In an oil-fired furnace, the combination of a burner, a two-stage air heater in the path of the waste gases, and means for supplying the burner with air which has passed completely through said ,heater and also with air which has passed only through the first-stage portion of the heater, both an; supplies being at the same pressure substantially as described.

8. In an oil-fired furnace, the combination of an oil-burner, means for delivering air around the nozzle of said burner in two distinct zones one outsidev the other, a two-stage air-heater in the path of the products of combustion, means for supplying the inner zone with air which has passed completely through the heater, and means for supplying the outer zone with air which haspassed only through the first stage of the heater, substantially as described.

a. In an oil-fired furnace, the combination of an oil burner, an air-heater in the path of the waste gases divided into two sections through one of which passes all the air supply intended for the combustion, a portion of said air being separately heated to a higher temperature in the other section of the heater, and means for conducting both air supplies at the same pressure separately to the burner with the hotter supply in immediate contact with the same, substantially as described.

5. In an oil-fired furnace, the combination of an oil burner, inner and outer air-delivery means arranged to form two air zones around said burner, a heater in the path of the waste gases comprising two sections for two-stage heating, means for supplying air from the second section to the inner zone. and means for supplying air from only the first section to the outer zone, substantially as described. 7

In testimony whereof I afiix my signature.

WILLIAH- HENRY OWEN. 

